左旋布比卡因与布比卡因腰麻在经尿道前列腺电切术中的比较

目的比较左旋布比卡因与布比卡因腰麻用于老年患者经尿道前列腺电切术的麻醉效果和并发症。方法选择择期行经尿道前列腺电切术的老年患者40例,年龄65～91岁,ASAⅠ～Ⅲ级,随机分为两组:L组,20例,0.5%左旋布比卡因1.5ml,B组,20例,0.5%布比卡因1.5ml,均行单次蛛网膜下腔注射。观察并记录感觉阻滞最高平面、到达感觉阻滞最高平面时间、感觉消退至L5的时间,运动神经阻滞时间、围术期血压与心率变化以及恶心、呕吐、寒战、皮肤瘙痒、呼吸抑制等副作用。结果所有患者麻醉镇痛完善。B组感觉阻滞和运动阻滞达到最高平面的时间明显短于L组(P0.05)。B组给药后10分钟到30分钟的平均动脉压显著低于L组(P0.05)。B组低血压和恶心的发生率显著高于L组(P0.05)。结论左旋布比卡因能满足老年患者TURP的麻醉要求,且血流动力学更稳定,副作用明显减少,更适合老年人的椎管内麻醉。     

小剂量布比卡因复合芬太尼腰麻在痔手术中的应用

目的探讨小剂量布比卡因复合芬太尼腰麻用于痔手术的麻醉效果及其不良反应。方法 择期行痔手术患者80例,随机分为2组,每组40例。A组采用0.5%布比卡因5 mg复合芬太尼20μg腰麻,B组采用0.5%布比卡因10 mg腰麻。观察并比较2组患者麻醉效果、血流动力学变化、下肢运动阻滞恢复时间和不良反应。结果2组患者麻醉效果均满意,A组麻醉后血压下降小于B组(P<0.05),下肢运动阻滞恢复时间短于B组(P<0.05)。低血压和恶心发生率A组低于B组(P<0.05)。结论小剂量布比卡因复合芬太尼20μg腰麻应用于痔手术麻醉效果满意,无明显不良反应。     

经尿道前列腺切除术患者鞘内布比卡因混合舒芬太尼麻醉的效果

经尿道前列腺切除术（TURP）目前常采用布比卡因腰麻，为避免布比卡因腰麻产生的血液动力学不稳定和长时间下肢肌肉松弛的不利因素，近年来尝试采用阿片类药物混合小剂量布比卡因用于腰麻。舒芬太尼是芬太尼的衍生物，与阿片类受体亲和力较芬太尼强，与芬太尼比较，舒芬太尼腰麻血液动力学平稳，而且能够在产生脊髓节段镇痛的同时保持下肢运动功能，TURP小剂量布比卡因混合舒芬太尼腰麻的效果有待进一步探讨。本研究拟观察TURP患者鞘内小剂量布比卡因混合舒芬太尼麻醉的效果，探讨适宜的布比卡因混合浓度。     

左旋布比卡因腰-硬联合阻滞在下肢手术的应用

目的探讨0.75%左旋布比卡因用于蛛网膜下隙阻滞的临床效果及安全性。方法随机选择ASAⅠ～Ⅱ级的40例骨科下肢手术患者(股骨干及髋关节大手术的患者),随机均分成两组:L组腰麻用药为0.75%左旋布比卡因15mg,容量为2.5ml;B组腰麻用药为0.75%布比卡因,剂量及容量同L组。术中必要时经硬膜外导管注入2%利多卡因。术中监测BP、HR、SpO2、RR的变化并观察围术期不良反应的发生。结果两组最高阻滞平面及到达时间、麻醉持续时间、肌松效果及达到最大肌松效果时间差异均无显著意义。两组均无神经系统的不良反应。结论0.75%左旋布比卡因用于腰-硬联合麻醉骨科下肢手术安全有效,效果与0.75%布比卡因相比差异无显著意义。     

小剂量布比卡因复合芬太尼腰-硬联合麻醉用于急诊剖宫产的临床观察

目的 探讨小剂量布比卡因复合芬太尼腰-硬联合麻醉在急诊剖宫产手术中应用的可行性.方法 单胎急诊产妇108例,随机均分为布比卡因复合芬太尼组(BF组)和布比卡因组(B组).药物分别为0.75%布比卡因5 mg加芬太尼20μg和0.75%布比卡因7.5 mg.两组产妇均在右侧卧位下于L2～3间隙用针内针方法行腰麻,留置硬膜外导管备用.记录麻醉等待时间、最高平面、硬膜外追加药物的情况,术中心率、血压变化和麻黄碱的使用情况,并记录术中恶心呕吐、胸闷、呼吸困难等不良反应;记录手术医师和产妇对麻醉的评价以及术后下肢肌力完全恢复所需时间.结果 所有患者成功完成手术,无需改变麻醉方式或静脉辅助用药.BF组硬膜外腔追加药物率、低血压发生率和麻黄碱使用率明显少于B组(P＜0.01);麻黄碱平均用量明显少于B组(P＜0.05);恶心呕吐和胸闷的发生率明显低于B组(P＜0.05或P＜0.01);下肢肌力恢复到Bromage 0分的时间短于B组(P＜0.05).结论 0.75%布比卡因5 mg复合芬太尼20 μg腰-硬联合麻醉能为急诊剖宫产提供满意的麻醉.     

超小剂量布比卡因复合芬太尼腰麻用于肛肠疾病患者日间手术的可行性

目的 探讨超小剂量布比卡因复合芬太尼腰麻用于肛肠疾病患者日间手术的可行性.方法 ASAⅠ～Ⅱ级肛肠手术患者60例,随机分成两组,分别采用0.75%布比卡因0.4ml+芬太尼15μg+50%葡萄糖0.05ml行腰麻(腰麻组)和传统骶管阻滞组1.2%利多卡因25～30ml(骶麻组).记录两组患者围术期血流动力学变化,和麻醉后患者感觉阻滞起效和持续时间,最大下肢运动阻滞强度,肛门松弛度,调查外科医师和患者满意度.手术后恶心、呕吐、尿潴留、瘙痒、头痛等不良反应.结果 腰麻组痛觉阻滞起效较骶麻组快.腰麻组痛觉阻滞持续时间较骶麻组长.低血压、恶心、呕吐、尿潴留发生率、肛门松弛度两组无明显差异.瘙痒发生率腰麻组高于骶麻组.医师和患者满意度腰麻组均高于骶麻组.结论 超小剂量布比卡因复合芬太尼腰麻起效快,痛觉阻滞时间长,运动阻滞少,不良反应发生率少,是肛肠疾病手术麻醉的适合方法,用于日间手术具有可行性.     

等剂量罗哌卡因、左布比卡因腰麻应用于剖宫产术中的比较

目的比较0.75%罗哌卡因和0.75%左布比卡因对剖宫产手术腰麻的临床效果。方法 160例ASA1～2级择期剖宫产手术患者随机分为0.75%罗哌卡因（R）组和0.75%左布比卡因（L）组。采用25G腰麻穿刺针,于L3～4间隙穿刺。监测两组感觉运动阻滞情况、麻醉效果及不良反应情况。结果 R组最大阻滞时间、最大运动阻滞时间均高于L组;而运动恢复时间,R组低于L组,两组比较差异有统计学意义（P〈0.05）。结论等剂量罗哌卡因和左旋布比卡因腰麻麻醉效果和不良反应差异无统计学意义,左旋布比卡因运动神经阻滞比罗哌卡因更完全,罗哌卡因则具有运动神经阻滞起效慢而恢复较快的特点。     

左旋布比卡因腰麻在剖宫产手术的应用

目的比较0.5%重比重左旋布比卡因与0.5%重比重布比卡因腰麻用于剖宫产手术的麻醉效果.方法选择ASA Ⅰ～Ⅱ级患者60例于腰麻下行择期剖宫产手术,随机、双盲均分为两组：L组用药0.5%重比重左旋布比卡因2.4 ml（12 mg）,B组用药0.5%重比重布比卡因2.4 ml（12 mg）.术中连续监测呼吸和循环状况,评估麻醉效应和维持时间,并观察围手术期不良反应的发生及新生儿情况.结果两组胸椎最高阻滞平面、术中运动神经阻滞级别、T11痛觉阻滞消失时间、腰麻的运动和感觉神经阻滞作用的消退时间比较均无显著性差异;两组腹腔牵拉反应时VAS评分比较无显著性差异（P＞0.05）;低血压发生率L组为20%,B组为23.3%;患者满意率L组为85%,B组为87%.新生儿Apgar 1分、5分的评分两组比较无显著性差异（P＞0.05）.结论与0.5%重比重布比卡因的比较,0.5%重比重左旋布比卡因腰麻用于剖宫产手术同样安全有效.     

小剂量布比卡因复合芬太尼腰-硬联合麻醉对剖宫产产妇血流动力学的影响

目的探讨应用FloTrac/Vigileo系统观察小剂量布比卡因复合芬太尼腰-硬联合麻醉对剖宫产产妇血流动力学的影响。方法 60例孕足月、单胎剖宫产产妇随机均分为两组:A组腰麻用药为布比卡因10mg;B组腰麻用药为布比卡因6mg复合芬太尼20μg。记录两组患者麻醉前（T₁）、麻醉后3min（T₂）、10min（T₃）、15min（T₄）、30min（T₅）、手术结束时（T₆）的心输出量（CO）、MAP和HR变化;观察麻醉效果、不良反应、新生儿1、5min Apgar评分。结果 T₂～T₆时A组CO、MAP明显降低于T₁时和B组（P<0.05）。B组低血压和寒战发生率明显低于A组（P<0.05）。两组麻醉效果、新生儿1、5minApgar评分差异无统计学意义。结论小剂量布比卡因复合芬太尼腰-硬联合麻醉行剖宫产术可维持血流动力学稳定,FloTrac/Vigileo系统可持续有效监测血流动力学。     

小剂量罗哌卡因复合芬太尼用于腰麻-硬膜外联合阻滞的临床观察

目的　观察小剂量罗哌卡因复合芬太尼用于腰麻 -硬膜外联合阻滞 (CSE)的可行性。方法　将 3 0例拟在CSE下行下肢手术患者随机分为两组。R组给予罗哌卡因 15mg ,RF组给予罗哌卡因 7.5mg 芬太尼 2 0 μg。两组均配成重比重液 3ml。观察两组运动及感觉阻滞程度及不良反应发生情况。结果　两组间感觉阻滞程度无显著差异。RF组运动阻滞程度明显低于R组。RF组麻醉后血流动力学稳定 ,不良反应少于R组。结论　小剂量罗哌卡因复合芬太尼用于CSE可以提供完善的感觉阻滞 ,术中血流动力学稳定 ,适用于下肢手术的麻醉。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.